This invention relates to a fuel control system for a gas turbine engine.
It is known, for example from EP-A-0132977 to effect shut-down of a gas turbine engine fuel system by causing substantially all of the fuel delivered by an engine-driven pump to be spilled back to pump inlet. In such a system the spillage of fuel results in a correspondingly rapid loss of system pressure. It is, however, desirable that system pressure, even though reduced, shall be maintained for sufficiently long as to enable servo operated equipment on the engine, as for example the compressor inlet guide vanes, to adopt operating positions appropriate to shut-down. It is also required that after shut-down the engine shall be able to windmill, as herein defined, without undue temperature rise of pumped fuel.